How much does the weather dictate your day?
If it is cloudy out are you more grumpy? Do you wait to make plans until it is a beautiful, sunny day?
What happens when a storm rolls in? Do you shut down, hide yourself away, or find yourself really anxious and tense?
The nature of our own mind is like a wide open, spacious sky. Pristine, clear, calm, expansive.
Thoughts and emotions are like the weather. Some days are good, some days are bad.
The purpose of meditation is to recognize that the weather plays out in the expanse of the sky, and it doesn't defile the sky in any way. The sky naturally accommodates whatever happens to roll through.
The sky is not more pure, or better, when it is cloud-free. In fact, some of the most beautiful sunsets happen when there are clouds to provide contrast and depth.
Don't fight your thoughts and emotions. Learn to make friends with them, so they are free in their own place.